Hollow stamp handle

ABSTRACT

A hollow, two-part elongated plastic handle including first and second matching parts parted along a longitudinal plane, each of the parts including a cap portion of uniform wall thickness, a gently tapered neck portion having a uniform wall thickness, an intermediate section interconnecting the cap portion and the larger end of the neck portion, an enlarged shoulder portion at the narrow end of the neck portion and a tendon portion suspended from the shoulder portion and having uniform wall thickness and gently tapering to a smaller cross-section at its outer end, remote from the shoulder portion.

[ Sept. 18, 1973 HOLLOW STAMP HANDLE [75] inventors: Edward J. Gibbons,381 Summer St.,

Brighton; Norman 0. Daigle, Fitchburg, both of Mass.

[73] Assignee: said Gibbons, by said Daigle,

Brighton, Mass.

[22] Filed: Nov. 1, 1971 [21] Appl. No.: 194,650

[56] I Reierences Cited I UNITED STATES PATENTS 3,302,566 2/1967Blanchet 101/405 1,730,820 10/1929 Holden 145/61 c 2,799,527 7/1957Cederblad 145/64 x 2,920,682 1/1960 Lindberg 46/76 R x 2,807,437 9/1957Roush 29/463 x 2,308,627 1/1943 Richenbacher 145/61 C X 483,865 10/1892Potter et al. 145/61 .1

2,146,415 2/1939 Bradley 145/61 C 1,974,337 9/1934 Magnawi 145/61 .1 X2,646,748 7/1953 Brown, Jr. 101/405 X Primary Examiner-Robert E. PulfreyAssistant Examiner Eugene H. Eickholt [57] ABSTRACT A hollow, two-partelongated plastic handle including first and second matching partsparted along a longitudinal plane, each of the parts including a capportion of uniform wall thickness, a gently tapered neck portion havinga uniform wall thickness, an intermediate section interconnecting thecap portion and the larger end of the neck portion, an enlarged shoulderportion at the narrow end of the neck portion and a tendon portionsuspended from the shoulder portion and having uniform wall thicknessand gently tapering to a smaller cross-section at its outer end, remotefrom the shoulder portion.

5 Claims, 5 Drawing Figures PATENTEB sm 8 I975 HOLLOW STAMP HANDLE FIELDOF INVENTION This invention relates to an improved plastic handle, andmore particularly to such a handle for rubber stamps.

BACKGROUND OF INVENTION Handles, particularly those used in rubberstamps, are typically made of wood. Such handles generally are formedwith a knob at the top to fit the hand of the user, a neck, and a tendonof reduced cross-section extending from the neck and designed to beinserted in a hole in the rubber stamp body Those wooden handles arerelatively expensive due to the high material, manufacturing, andfinishing costs involved. It is generally difficult to maintain precisetolerances on wooden han-- dles, because of the nature of the material.This is especially important in regards to the tendon portion which issized to be inserted into the hole provided in the rubber stamp body. Inaddition, because of the nature of the wood the body may crack or splitwhen the handle is hammered into the body or afterwards. Attempts tomake the handles out of plastic material have met with indifferentsuccess. For example, on one approach the entire handle is molded in onepiece except for a small opening at the top of the handle. That openingis closed by means of a snap fit cap. The handle is hollow and tends towarp and crack. The cap often pops off when the handle is struck with ahammer to fit the tendon into the hole provided in the body. Inaddition, the handle often breaks off at the tendon within a .few daysafter assembly. The flat portion on the front of the handle whichusually carries printed information of some sort, usually including theword FRONT, often is not strong enough to withstand the printing action,even though that portion is made extra thick. The basis of thisinvention is the discovery that the reason for the breaking of thetendon is that the hole in which it is inserted in the wooden bodyspreads to receive the tendon when it is inserted. Then after insertionthe hole shrinks and squeezes the tendon. The pressure on the tendoncauses stresses that result in the breaking of the tendon. It was alsodiscovered that cracking and breaking of the prior art plastic handleswas due, at least in part, to inherent weakness in the handle resultingfrom non-uniformity of the wall thickness and to stresses occurring atcertain points in the handle.

SUMMARY OF INVENTION It is therefore an object of this invention toprovide an improved inexpensive, plastic handle of uniformly ruggedtwo-part construction.

It is a further object of this invention to provide such a handle whichis of uniform quality, easy to insert, able to withstand the shocks ofassembly and use, and capable of having printing done on its flat frontface without damage tothe structure.

The invention features a hollow two-part elongate plastic handle formedof first and second matching parts parted along a longitudinal plane.Each of the parts includes a cap portion of uniform wall thickness and atapered neck portion having uniform wall thickness. An intermediatesection interconnects the cap portion with the larger end of the neckportion and there is an enlarged shoulder portion at the narrow end ofthe neck portion. A tendon portion is suspended from the shoulderportion and has a uniform wall thickness. The tendon tapers to a smallercross-section at its outer end, remote from the shoulder portion.

DISCLOSURE OF PREFERRED EMBODIMENT Other objects, features andadvantages will occur from the following description of a preferredembodiment and the accompanying drawings, in which:

FIG. 1 is an axonometric view of an assembled hollow, two-part elongatedplastic handle according to this invention;

FIG. 2 is a side elevational view of one part of the handle;

FIG. 3 is a front elevational view of the part shown in FIG. 1;

FIG. 4 is a front elevational view of the other part of the handle shownin FIG. 1; and

FIG. 5 is a side elevational view of the part shown in FIG. 4.

The invention may be accomplished with a hollow two-part elongatedplastic handle including first and second parts separated along alongitudinal plane passing through the longitudinal central axis of thehandle. Each of the parts includes a cap portion of uniform wallthickness, a gently tapered neck portion having uniform wall thickness,and an intermediate section interconnecting the cap portion and thelarger end of the neck portion. At the lower end of the neck portion,there is an enlarged shoulder portion extending from which is a tendonportion having uniform wall thickness and tapered to asmallercross-section at its outer end, remote from the shoulder portion. One ofthe parts may include one or more alignment pins on its mating surfaceand the other part a like number of alignment holes for receiving thepins. A raised bead may be provided on the mating surface of one of theparts for enabling the two parts to be welded together. In one of thetwo parts the intermediate section may include an expansive planar areawhich is provided to carry some printed legend, such as for example, theword FRONT and the manufacturers brand name, or similar information.That planar area generally is contained wholly on one or the other ofthe parts. In addition to being tapered, the tendon may also include abeveled edge at its lower end to facilitate its placement in the matinghole in the body. For increased strength, all of the junctions betweensurfaces may be formed with radii to reduce stress. The enlargedreinforced shoulder portion provides increased mass and strength at theinterface between the handle and the body of the rubber stamp, so that agreater portion of the burden on the tendon may be assumed by theshoulder.

The invention may be embodied in a two-part plastic rubber stamp handle10, FIG. 1, including a cap portion 12, gently tapering neck portion 14,and intermediate member 16 interconnecting cap 12 and neck 14. At thelower end of neck portion 14 is an enlarged reinforced shoulder 18 fromwhich extends a tendon Z0. Tendon 20 is tapered to a reducedcross-sectional area at its outer end most remote from shoulder 18 andcontains at that outer end a bevel 22 to facilitate its being fittedinto the mating hole in the rubber stamp body. Eahc junction betweensurfaces is formed with a radius 24 to increase the strength of handle10 and reduce stress concentration.

Handle 10 includes two parts 26 and 28 which are separated along thelongitudinal plane through the central longitudinal axis of handle asshown by the parting line 30. Intermediate section 16 may include anexpansive planar area 32, preferably contained entirely on one or theother of parts 26 or 28. Planar area 32 is provided for carrying someprinted legend 34 such as the word FRONT, for example, indicating whichside of the rubber stamp is the front side. Previously, planar area 32would have to be constructed using thicker walls or some sort ofreinforced material in order to bear the forces exerted on it by theprinting operation without deforming or distorting the handle. However,with the construction shown in FIG. 1, the part 26 may be placed withthe inside of area 32 against a back-stop while area 32 is being printedso that the force of the printing action need not be borne by the handlestructure alone.

Part 26 is formed with a wall 36, FIGS. 2 and 3, which is uniformlyapproximately 0.085 inches in thickness. Preferably, the thickness ofthe wall below the shoulder 18 hasqan increased thickness of 0.125inches for added durability. All radii 24 are approximately 0.62 inches.The mating edge 38 of wall 36 includes a plurality of alignment pins 40and a bead 42 having a triangular cross-section which provides thematter to form a weld between the two parts 26 and 28. The lower end ofneck 14 proximate shoulder 18 is typically approximately 0.5 inches indiameter, while the shoulder itself is an enlarged 0.6 inches indiameter. Tendon is tapered such that at its outer end it isapproximately 0.29 inches in diameter. Part 28, FIGS. 4 and 5, has ashape similar to that of part 26 and is formed of a wall 36' similar towall 36. The mating edge 38' of wall 3, however, contains no bead 42. Inaddition, edge 38 contains four alignment holes 44 for receivingalignment pins 40 on part 26. All of the dimensions on part 28,including those of radii 24, are the same as those given with referenceto part 26, FIGS. 4 and 5. It is not necessary that there be fouralignment pins 40 and four alignment holes 44 for even one alignment pinand one alignment hole will provide some assistance in properly fittingparts 26 and 28 together, and two or more pins and holes are definitiveof the relative positions of parts 26 and 28. The pins may be on part 28instead of on part 26 and thus also the holes may be on part 26 insteadof on part 28. The weld bead 42 also may alternatively be disposed onmating edge 38' of part 28 or may be eliminated entirely, especially ifa method other than welding is going to be used to secure parts 26 and28 together.

Other embodiments will occur to those skilled in the art and are withinthe following claims:

What is claimed is:

1. A hollow two-part, longitudinally elongated, plastic handle forrubber stamps and the like comprising means forming first and secondmatching handle parts parted along a longitudinal plane,

each of said parts being made ofplastic and including a cap portion ofuniform wall thickness,

a longitudinally tapered neck portion having a uniform wall thickness,

an intermediate section interconnecting said cap portion and the largerend of said neck portion,

an enlarged shoulder portion with a greater wall thickness than saidneck wall thickness at the narrow end of said neck portion, and

a tendon portion suspended from said shoulder portion and having uniformwall thickness and having a smaller cross-section area than the shoulderportion at its outer end remote from said shoulder portion,

the intermediate section of one of said first and second partscomprising an expansive planar area therein,

means integrally formed on each handle part for securing the partstoeach other, and

the assembled matching parts forming an enclosed empty volume.

2. The handle of claim 1 in which one of said parts includes a pluralityof alignment pins and the other includes a plurality of alignment holesfor receiving said pll'lS.

3. The handle of claim I in which said tendon portion has a beveled edgeat its outer end to facilitate its placeof said matching parts.

1. A hollow two-part, longitudinally elongated, plastic handle forrubber stamps and the like comprising means forming first and secondmatching handle parts parted along a longitudinal plane, each of saidparts being made of plastic and including a cap portion of uniform wallthickness, a longitudinally tapered neck portion having a uniform wallthickness, an intermediate section interconnecting said cap portion andthe larger end of said neck portion, an enlarged shoulder portion with agreater wall thickness than said neck wall thickness at the narrow endof said neck portion, and a tendon portion suspended from said shoulderportion and having uniform wall thickness and having a smallercross-section area than the shoulder portion at its outer end remotefrom said shoulder portion, the intermediate section of one of saidfirst and second parts comprising an expansive planar area therein,means integrally formed on each handle part for securing the parts toeach other, and the assembled matching parts forming an enclosed emptyvolume.
 2. The handle of claim 1 in which one of said parts includes aplurality of alignment pins and the other includes a plurality ofalignment holes for receiving said pins.
 3. The handle of claim 1 inwhich said tendon portion has a beveled edge at its outer end tofacilitate its placement in a mated hole.
 4. The handle of claim 1 inwhich each said part includes a radius at each surface junction toreduce stress.
 5. Device in accordance with claim 1 wherein said meansfor securing are incorporated in the wall edges of said matching parts.